<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        .father {
            width: 100%;
            height: 60vw;
            background-color: pink;
            /* 在父盒子中开启弹性布局 */
            display: flex;
            /* 默认主轴方向是横向 */
            justify-content: space-evenly;
            /* 交叉轴 */
            align-items: center;
        }
        .one {
            /* 单独设置交叉轴对齐方式 */
            align-self: flex-start;
        }
        .two {            
            align-self: center;
            /* 分配剩余尺寸的1份 */
            flex: 1;
        }
        .three {
            align-self: flex-end;
        }
        .father div {
            width: 20vw;
            height: 20vw;
            background-color: orange;
            border: 1px black solid;
            box-sizing: border-box;
        }
    </style>
</head>
<body>
    <div class="father">
        <div class="one">1</div>
        <div class="two">2</div>
        <div class="three" >3</div>
    </div>
</body>
</html>